Options must all come before arguments, once a
single positional argument or subcommand is parsed,
all remaining arguments are treated as positionals.
A `--` option can be passed if the first positional
one needs starts with -.

Options and arguments can be interspersed, but if
a given option is not found, it is treated as a
positional argument. This is sometimes useful if
one is passing through most options to another tool,
but are supplying just a few of their own options.